Process for making finely divided metal oxides



Patented Mar. 22, 1932 UNITED STATES PATENT OFFICE ALWIN MITTASCH AND RICHARD LUCAS, OF MANNHEIM, AND ROBERT GRIESSBACH,

OF LUDWIGSHAFEN-ON-THERHINE, GERMANY, ASSIGNORS TO I. G. FARBENIN- DUSTRIE AKTIENGESELLSCHAFT, OF FRANKFORT-ON-THE-MAIN, GERMANY, A COR PORATION OF GERMANY PROCESS FOR MAKING FINELY DIVIDED METAL OXIDES No Drawing. Original application filed May 20, 1925, Serial No. 31,691, and in Germany May 23, 1924. Divided and this application filed September 18, 1926. Serial No. 136,374.

The subject matter of this application has been divided out and transferred hereto from our copending application Ser. No. 31,691, filed May 20th, 1925.

-" It has been shown in the said patent application that oxids of metallic elements can be obtained in a state of extremely fine division by burning a volatilizable. carbonyl alone or together with a volatilizable halide of ametallic element in the presence of a vola-.

tilizable or gaseous combustible matter. The term metallic element is intended to include metals such as iron, chromium, aluminium, titanium and others and also silicon which as an element has a metallic character.

We have found that in a manner similar to the proce s described and claimed in our application Ser. No. 31,691 filed May 20th, 19:25, oxids of metallic elements in a state of extremel finedivision can be obtained by burning a volatile halide of a metallic element or mixtures of several such halides in the presence of a volatilizable or gaseous combustible matter, which combustible matter may be. an inflammable gas or vapor and suitably mixed with the halide.

The powders obtained by the process here described are valuable for many purposes. For example they may be used as a mineral pigment coloring matter, or as a polish, or as catalysts, or for the preparation of very finely divided metals, or the like.

he process according to this invention is applicable for example to ferric chlorid, chr

omyl chlorid, aluminium chlorid, sgicgn,

tatrachlorid, titanium chlorid or mixtures of such compounds, which may be brought into a flame in a finely divided condition, into [,which flame, besides, nonvolatile powders may be introduced for shading the product. For example, purified coal gas is loaded with titanium chlorid vapors and ignited in the air. Highly dispersed titanic oxid is r produced which, owing to its high specific volume, is carried along with the gas current and may be separated in a chamber provided with several floors consisting of or hearing filtering materials. The particles are here separated in accordance with their size While the gases of combustion leave the chamber. Or, the titantic oxid may be precipitated in dust chambers with the aid of high tension electric discharges, or in any other suitable manner. Depending on the temperature of the combustion and the duration of the stay of the oxid in the combustion chamber, the oxid is obtained in varying degrees of dis persion, whereby, in the case of for example iron oxid, different reddish shades can be obtained.

We claim:

1. The process of producing finely divided titanic oxid which comprises burning titanium chlorid distributed in an atmosphere of oxidizing gas in a flame produced by a gasitied combustible matter.

The process of producing finely divided titanic oxid which comprises burning tit-anium chlorid distributed in an atmosphere of oxidizing gas in a flame produced by purified coal gas.

In testimony whereof we have hereunto set our hands.

ALWIN MITTASCH. RICHARD LUCAS. ROBERT GRIESSBACH. 

